It began as a peaceful candlelight vigil to mourn the shooting death of an unarmed black teenager. But he -- Sunday night with rioting and looting tensions spilled over into violence in the Saint Louis suburb of Ferguson. -- eighteen year old Michael Brown was shot by a police officer on Saturday. Police used tear gas to break up crowds several businesses were vandalized and robbed. Brown was supposed to start his first day of college classes today. Now more aware and certainly everything -- couldn't -- -- they -- is to -- engine program couldn't. -- -- -- Brown was walking with a friend in broad daylight to his grandmother's house in a predominately African American neighborhood outside Saint Louis it was a good -- -- that they have for no reason. Brown's friend says the police officer drove by and told them to get off the street an argument began after the police officer stepped out of his car. An officer Dan reached out they grabbed his arm to pull out and to -- Episode that was like officers pulling -- inside the court he's trying to pull away. But police say the officer a six year veteran of the force was pushed back into the car and physically assaulted. Brown was killed in the street about 35 feet away from the squad car he was hit by more than one bullet. And again today demonstrators gathered outside the Ferguson police department. While the town's streets all demanding justice for brown. This is a very. Complicated investigation. As it should be we need to make sure that this investigation is done right. The FB I will conduct its own parallel investigation into what happened on Saturday afternoon. Karen Travers ABC news Washington.

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